Nozzle device for producing a fluid jet

ABSTRACT

The present invention relates to a nozzle device for producing a jet of a fluid for the insertion of weft threads into a shed on a loom, the nozzle device comprising an inner portion and an outer portion surrounding the inner portion, there being provided between the inner portion and the outer portion a chamber which contains a fluid, which chamber is rotationally symmetrical about the axis of the nozzle, and which chamber has apertures therein for supplying the fluid and a fluid exiting nozzle aperture surrounding a bore through which the weft thread passes propelled by said fluid as it exits from said nozzle aperture.

United States Patent i191 Keldany Feb. 4, 1975 [54] NOZZLE DEVICE FORPRODUCING A 3,559,860 2/1971 East 226/97 FLUID J 3,576,284 4/1971Fellows 226/97 3,633,808 l/l972 Svaty 226/97 [75] Inventor: Rachld eany, ri 3,655,862 4/1972 Dorschner et al. 226/97 Switzerland [73]Assignee: Ruti Machinery Works Ltd., Primary Examiner-Allen N. Knowles(formerly Caspar Honegger), Attorney, Agent, or Firm-Donald D. DentonRuti/ZH', Switzerland [22] Filed: May 1, 1973 [57] ABSTRACT [21] Appl.No.: 356,103 I The present invention relates to a nozzle device forproducing a jet of a fluid for the insertion of weft [30] ForeignApplication Priority Data threads intoa shed on a loom, the nozzle devce comprising an inner portion and an outer portion sur May 29, i972Switzerland 7395/72 rounding the inner portion, there i g p id rtween'the inner portion and the outer portion a chame I erw 1C contalnsau ,.W C c am er ,5 tat 2% F 8 b h'h fl'd h'h h b l 5 ally symmetricalabout the axis of the nozzle, and 1 0 care l which chamber has aperturestherein for supplying the 19/66 T fluid and a fluid exiting nozzleaperture surrounding a References Cited bore through which the weftthread passes propelled by said fluid as it exits from said nozzleaperture.

8 Claims, 2 Drawing Figures PATEMED 7 3,863,822

VELOCITY CHAMBER LEN GTH NOZZLE DEVICE FOR PRODUCING A FLUID JETBACKGROUND It is known to insert weft threads into an open shed, asindividual picks, by means of a jet of air or water. This type of weftinsertion, employing means known at the present day, has thedisadvantage that any sharply focused" jet which can be produced canhave only limited length, so that broad fabrics cannot be manufacturedin this manner.'Art which shows the use of air and water jets aredisclosed in the following patents:

US. Pat. No. 2,796,085 US. Pat. No. 3,l80,368.

SUMMARY This disadvantage is obviated by the present invention. Thepresent invention is characterized in that the chamber has between theinner portion and the outer portion of the nozzle device, extendingrearwardly away from the nozzle aperture, an alignment or "aiming"portion which determines the direction of the jet and which is prolongedin the form ofa storage portion, the apertures for supplying the fluidto the chamber being located in the chamber zone remote from the nozzleaperture.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be describedwith reference to an example of embodiments and with reference to thedrawings, in which:

FIG. 1 is a longitudinal section through the nozzle device which issymmetrical in shape; and

FIG. 2 illustrates the important features of the chamber containing thefluid, the velocity distribution of the fluid in the chamber also beingshown.

DESCRIPTION OF PREFERRED EMBODIMENTS The nozzle device 11 shown in FIG.1 has a jet or nozzle needle 12 affording an inner part or portion. Thenozzle needle or inner portion 12 is surrounded by an outer part orportion which, according to this example of embodiment, embraces anozzle insert 13 and a nozzle head 16. A securing screw or threaded cap32 is also provided. The inner portion 12, the nozzle insert 13, and thenozzle head 16 of the outer portion constitute, or define together, afluid chamber 14. Apertures 15 serve for feeding a fluid from a fluidsupply zone 15a into the chamber 14. A fluid supply source not shownconveys the fluid to the supply zone 15a through fluid supply conduit15b from a standard fluid feeding device 150. The nozzle insert 13 andthe nozzle needle 12 are united and held in operation position by meansof the nozzle head 16 and the securing screw 32. The screw 32 is adaptedto be screwed through the agency of the screw thread 33 to threadedportion of head 16. When the securing screw is in a tightened condition,the nozzle insert presses against packings I7 and provides forpreventing the escapement ofthe fluid out of the nozzle device 11. Thenozzle device can be secured to the loom by means ola support rod 19.The nozzle needle 12 is rotatable about a pivot line 18 relative to thenozzle insert 13 and, optionally, also the nozzle head 16 along the saidpivot line 18. A weft thread is guided through the bore 20 formed in thenozzle needle 12. As is shown in FIG. 1, the nozzle needle I2 is adaptedto be inserted into the nozzle insert 13 from the left-hand side.

The fluid chamber 14 is symmetrical in rotation and comprises a storageportion and an aligning or aiming" portion, the longitudinal sections ofwhich are delimited by walls 21, 22 and by curved portions of walls 23,24. In the direction of the axis 18, delimitation of the storage portionis afforded approximately by dashed boundary lines 25, 26, anddelimitation of the guiding portion by dashed boundary lines 26, 27. Anannular nozzle aperture 28 formed between the adjacent inside portion ofnozzle insert I3 and the outside portion of the needle nozzle 12coincides with the boundary line 27 through which the fluid exits as ajet from said chamber. An eyelet 30 may be provided with a small degreeof spacing from the nozzle aperture 28.

The design of the nozzle is discussed further in detail with referenceto FIG. 2. In the portion of FIG. 2 designated as A, the curved portionsof walls 23 and 24 extending between the boundaries 26 and 27 arerepresented as component portions of parabolic curves 31 and 32 in theirflow pattern, the foci of which are displaced in the axial direction.Thus, it may be said that the opening of the aligning portion toward thenozzle aperture 28 diminishes continuously by values becomingprogressively smaller. Toward the left, away from the boundary line 26,the delimiting portions 21, 22 of the cross-section of the storage partof the chamber 14 extend rectilinearly. Each of the walls 21, 22 forms atangent 21 and 22, respectively, in each instance to one of theparabolas 31 and 32 (see A of FIG. 2).

The chamber 14 is symmetrically rotational in shape, the delimitingportions of which follow a configuration which is rectilinear in respectof the wall 21, 22 and curved in respect of the parabola portions 23,24. If a fluid, for example a liquid, is routed through the apertures 15into the chamber 14, and through the latter, then the velocity patternof the liquid is that represented by the curve 33 in the portion B ofFIG. 2. The velocity is plotted in B of FIG. 2 as ordinate, as afunction of location, taken in the direction of the axis 18. It will bevappreciated that, directly at the boundary line 26, the acceleration ofthe fluid increases and that it reaches its maximum value between theboundary lines 26 and 27.

On inserting the weft threads by the nozzle device into the shed, highpressure is for a short time imparted to the liquid. Thereby, it flowsthrough the apertures 15 into the chamber 14 conveyed by fluid feedingdevice 15c, whereby a jet is emitted out of the nozzle aperture 28 for ashort period of time. The said jet of fluid engages the weft threadinserted through the bore 20 around its periphery, entrains it andinserts it into the shed. That quantity of liquid already available inthe chamber 14 on commencement of the increase in the fluid pressureundergoes no noticeable change in direction in respect of its movement,so that the minimum of turbulence is set up in it, the result of thisbeing an extremely uniform jet travelling at extremely high velocity,which propels the weft thread into the shed. The liquid flowing inthrough the apertures 15 must, on the other hand, be deflected from thevery outset, whereby there may be produced turbulent streams which couldbe detrimental to the formation of a uniform jet. Thus, in a preferredembodiment of the present invention, the volume of the chamber 14 is socalculated that it is at least approximately equal to the quantity ofliquid required for inserting an individual pick.

On the other hand, it is also possible to design only the curved portion24 to be parabolic and thedelimiting portion 23 to be rectilinear. Thereis then obtained a shape of the chamber 14 the longitudinal section ofwhich has the straight portion 35. The latter may, at the location ofthe nozzle aperture 28, be the tangent to the curve 31 according to thefirst embodiment. The advantage of a nozzle having an inner wall, thelongitudinal section of which is rectilinear, consists in that such anozzle is less expensive to manufacture .and nevertheless affords a jetof high quality.

The design of the walls of the chamber 14, in particular in the vicinityof the nozzle aperture 28, must be effected with maximum accuracy. Inorder to be able to compensate for any small deviations within thebounds of the degree of accuracy achievable, the nozzle needle 12 andthe nozzle insert 13 are rotatable about the pivot 18 relative to eachother. This may for example be effected by loosening the releasablescrew 32 and, thereupon, manually rotating the front portion 34 of thenozzle insert 13. After the optimum setting has been found, the portions12, 13 are locked by retightening the screw 32.

In order to still further improve the jet emerging out of the nozzle 28,the edges of the material'at the location of the delimiting portion 27may be deactivated so that there is no turbulance as the fluid flows outof the annular opening formed by the nozzle aperture.

It will be appreciated that the nozzle according to the presentinvention is suitable above all for a jet of liquid. However, also inthe event of employment ofa gaseous fluid, the nozzle according to theinvention produces a jet which is sharply focused over a considerablelength.

This disclosure of preferred embodiments and modifications of theinvention is to be interpreted as illustrative of forms the inventionmay take and other modifications will readily occur to those skilled inthe art. The invention is not to be restricted except by the scope ofthe appended claims wherein the novel features desired to be protectedby Letters Patent are set forth.

What is claimed is:

l. Nozzle device for producing a jet of fluid for inserting weft threadsinto a shed on a loom, the said nozzle device comprising an innerportion and an outer portion symmetrically surrounding said innerportion, said inner and outer portions defining a ring shaped nozzleaperture for ajet of fluid to flow out, there being defined between thesaid inner portion and the said outer portion a chamber which containsthe weft thread propelling fluid, said outer portion being formed with aplurality of apertures for supplying the fluid to said chamber from afluid source, said chamber having a front and a rear zone with its frontzone extending rearwardly away from said nozzle aperture and forming anaiming" portion for determining the direction of the flow of'said jet offluid, and which is prolonged by said rear zone forming a storageportion, the apertures for supplying the fluid to said chamber beinglocated in said rear zone remote from the nozzle aperture, said aimingportion being elongated and delimited by two walls at least one of whichis conical and that converge with respect to each other to produce asubstantially uniform decrease in the cross-section of the aimingportion in'the direction of the nozzle aperture, a bore in said innerportion for passage of said weft thread to be propelled by said jet offluid passing from said nozzle aperture, and a means for supplying saidfluid flow to said chamber.

2. Nozzle device according to claim 1 in which the delimiting of theaiming portion by said two walls produc'es a configuration of the flowvelocity pattern which is defined by two parabolas that are offsetrelative to each other in the axial direction.

3. Nozzle device according to claim 1 in which the I storage portion isdelimited by two walls including an acute angle with the nozzle axis andapproaching each other in the direction towards the nozzle aperture.

4. Nozzle device according to claim 1 for the insertion of weft threadsby means of a liquid, in which the volume of said chamber is at leastapproximately equal to the volume of the quantity of liquid required forthe insertion of the weft thread being drawn through said bore.

5. Nozzle device according to claim 1 in which the inner portion and theouter portion are rotatable relative to each other.

6. Nozzle deviceaccording to claim 5 in which said chamber is formed bythe outer surface of the inner portion and the inner surface of theouter portion, and the inner portion is adapted to be inserted in theaxial direction into the outer portion and is adapted to be held firmlyin relationship to the outer portion by means of a releasable securingscrew.

7. Nozzle device according to claim 1 in which the foremost delimitingportions of the nozzle aperture are constituted by deactivated edges.

8. Nozzle device according to claim 1 in which the two walls thatdelimit the storage portion are continued rectilinearly from thelocations of the transition to the aiming portion and abut tangentiallywith the walls of the aiming portion.

1. Nozzle device for producing a jet of fluid for inserting weft threadsinto a shed on a loom, the said nozzle device comprising an innerportion and an outer portion symmetrically surrounding said innerportion, said inner and outer portions defining a ring shaped nozzleaperture for a jet of fluid to flow out, there being defined between thesaid inner portion and the said outer portion a chamber which containsthe weft thread propelling fluid, said outer portion being formed with aplurality of apertures for supplying the fluid to said chamber from afluid source, said chamber having a front and a rear zone with its frontzone extending rearwardly away from said nozzle aperture and forming an''''aiming'''' portion for determining the direction of the flow of saidjet of fluid, and which is prolonged by said rear zone forming a storageportion, the apertures for supplying the fluid to said chamber beinglocated in said rear zone remote from the nozzle aperture, said aimingportion being elongated and delimited by two walls at least one of whichis conical and that converge with respect to each other to produce asubstantially uniform decrease in the cross-section of the aimingportion in the direction of the nozzle aperture, a bore in said innerportion for passage of said weft thread to be propelled by said jet offluid passing from said nozzle aperture, and a means for supplying saidfluid flow to said chamber.
 2. Nozzle device according to claim 1 inwhich the delimiting of the aiming portion by said two walls produces aconfiguration of the flow velocity pattern which is defined by twoparabolas that are offset relative to each other in the axial direction.3. Nozzle device according to claim 1 in which the storage portion isdelimited by two walls including an acute angle with the nozzle axis andapproaching each other in the direction towards the nozzle aperture. 4.Nozzle device according to claim 1 for the insertion of weft threads bymeans of a liquid, in which the volume of said chamber is at leastapproximately equal to the volume of the quantity of liquid required forthe insertion of the weft thread being drawn through said bore. 5.Nozzle device according to claim 1 in which the inner portion and theouter portion are rotatable relative to each other.
 6. Nozzle deviceaccording to claim 5 in which said chamber is formed by the outersurface of the inner portion and the inner surface of the outer portion,and the inner portion is adapted to be inserted in the axial directioninto the outer portion and is adapted to be held firmly in relationshipto the outer portion by means of a releasable securing screw.
 7. Nozzledevice according to claim 1 in which the foremost delimiting portions ofthe nozzle aperture are constituted by deactivated edges.
 8. Nozzledevice according to claim 1 in which the two walls that delimit thestorage portion are continued rectilinearly from the locations of thetransition to the aiming portion and abut tangentially with the walls ofthe aiming portion.